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Surveillance for chronic fatigue syndrome : four U.S. cities, September 1989 through August 1993: PROBLEM/CONDITION: Although chronic fatigue syndrome (CFS) has been recognized as a cause of morbidity in the United States, the etiology of CFS is unknown. In addition, information is incomplete concerning the clinical spectrum and prevalence of CFS in the United States. REPORTING PERIOD COVERED: This report summarizes CFS surveillance data collected in four U.S. cities from September 1989 through August 1993. DESCRIPTION OF SYSTEM: A physician-based surveillance system for CFS was established in four U.S. metropolitan areas: Atlanta, Georgia; Wichita, Kansas; Grand Rapids, Michigan; and Reno, Nevada. The objectives of this surveillance system were to collect descriptive epidemiologic information from patients who had unexplained chronic fatigue, estimate the prevalence and incidence of CFS in defined populations, and describe the clinical course of CFS. Patients aged > or = 18 years who had had unexplained, debilitating fatigue or chronic unwellness for at least 6 months were referred by their physicians to a designated health professional(s) in their area. Those patients who participated in the surveillance system a) were interviewed by the health professional(s); b) completed a self-administered questionnaire that included their demographic information, medical history, and responses to the Beck Depression Inventory, the Diagnostic Interview Schedule, and the Sickness Impact Profile; c) submitted blood and urine samples for laboratory testing; and d) agreed to a review of their medical records. On the basis of this information, patients were assigned to one of four groups: those whose illnesses met the criteria of the 1988 CFS case definition (Group I); those whose fatigue or symptoms did not meet the criteria for CFS (Group II); those who had had an identifiable psychological disorder before onset of fatigue (Group III); and those who had evidence of other medical conditions that could have caused fatigue (Group IV). Patients assigned to Group III were further evaluated to determine the group to which they would have been assigned had psychological illness not been present, the epidemiologic characteristics of the illness and the frequency of symptoms among patients were evaluated, and the prevalence and incidence of CFS were estimated for each of the areas. RESULTS: Of the 648 patients referred to the CFS surveillance system, 565 (87%) agreed to participate. Of these, 130 (23%) were assigned to Group I; 99 (18%), Group II; 235 (42%), Group III; and 101 (18%), Group IV. Of the 130 CFS patients, 125 (96%) were white and 111 (85%) were women. The mean age of CFS patients at the onset of illness was 30 years, and the mean duration of illness at the time of the interview was 6.7 years. Most (96%) CFS patients had completed high school, and 38% had graduated from college. The median annual household income/for CFS patients was $40,000. In the four cities, the age-, sex-, and race-adjusted prevalences of CFS for the 4-year surveillance period ranged from 4.0 to 8.7 per 100,000 population. The age-adjusted 4-year prevalences of CFS among white women ranged from 8.8 to 19.5 per 100,000 population. INTERPRETATION: The results of this surveillance system were similar to those in previously published reports of CFS. Additional studies should be directed toward determining whether the data collected in this surveillance system were subject to selection bias (e.g., education and income levels might have influenced usage of the health-care system, and the populations of these four surveillance sites might not be representative of the U.S. population). ACTIONS TAKEN: In February 1997, CDC began a large-scale, cross-sectional study at one surveillance site (Wichita) to describe more completely the magnitude and epidemiology of unexplained chronic fatigue and CFS.

Malaria surveillance : United States, 1993: PROBLEM/CONDITION: Malaria is caused by infection with one of four species of Plasmodium (P. falciparum, P. vivax, P. ovale, and P. malariae), which are transmitted by the bite of an infective female Anopheles sp. mosquito. Most malaria cases in the United States occur among persons who have traveled to areas (i.e., other countries) in which disease transmission is ongoing. However, cases are transmitted occasionally through exposure to infected blood products, by congenital transmission, or by local mosquito-borne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations. REPORTING PERIOD COVERED: Cases with onset of illness during 1993. DESCRIPTION OF SYSTEM: Malaria cases confirmed by blood smear are reported to local and/or state health departments by health-care providers and/or laboratories. Case investigations are conducted by local and/or state health departments, and the reports are transmitted to CDC. RESULTS: CDC received reports of 1,275 cases of malaria in persons in the United States and its territories who had onset of symptoms during 1993; this number represented a 40% increase over the 910 malaria cases reported for 1992. P. vivax, P. falciparum, P. ovale, and P. malariae were identified in 52%, 36%, 4%, and 3% of cases, respectively. The species was not determined in the remaining 5% of cases. The 278 malaria cases in U.S. military personnel represented the largest number of such cases since 1972; 234 of these cases were diagnosed in persons returning from deployment in Somalia during Operation Restore Hope. In New York City, the number of reported cases increased from one in 1992 to 130 in 1993. The number of malaria cases acquired in Africa by U.S. civilians increased by 45% from 1992; of these, 34% had been acquired in Nigeria. The 45% increase primarily reflected cases reported by New York City. Of U.S. civilians who acquired malaria during travel, 75% had not used a chemoprophylactic regimen recommended by CDC for the area in which they had traveled. Eleven cases of malaria had been acquired in the United States: of these cases, five were congenital; three were induced; and three were cryptic, including two cases that were probably locally acquired mosquito-borne infections. Eight deaths were associated with malarial infection. INTERPRETATION: The increase in the reported number of malaria cases was attributed to a) the number of infections acquired during military deployment in Somalia and b) complete reporting for the first time of cases from New York City. ACTIONS TAKEN: Investigations were conducted to collect detailed information concerning the eight fatal cases and the 11 cases acquired in the United States. Malaria prevention guidelines were updated and disseminated to health-care providers. Persons who have a fever or influenza-like illness after returning from a malarious area should seek medical care, regardless of whether they took antimalarial chemoprophylaxis during their stay. The medical evaluation should include a blood smear examination for malaria. Malaria can be fatal if not diagnosed and treated rapidly. Recommendations concerning prevention and treatment of malaria can be obtained from CDC.

Tetanus surveillance : United States, 1991-1994: PROBLEM/CONDITION: Despite the widespread availability of a safe and effective vaccine against tetanus, 201 cases of the disease were reported during 1991-1994. Of patients with known illness outcome, the case-fatality rate was 25%. REPORTING PERIOD COVERED: 1991-1994. DESCRIPTION OF SYSTEM: Physician-diagnosed cases of tetanus are reported to local and state health departments, the latter of which reports these cases on a weekly basis to CDC's National Notifiable Disease Surveillance System. Since 1965, state health departments also have submitted supplemental clinical and epidemiologic information to CDC's National Immunization Program. RESULTS: During 1991-1994, 201 cases of tetanus were reported from 40 states, for an average annual incidence of 0.02 cases per 100,000 population. Of the 188 patients for whom age was known, 101 (54%) were aged > or = 60 years and 10 (5%) were aged < 20 years. No cases of neonatal tetanus were reported. Among adults, the risk for tetanus increased with age; the risk for persons aged > or = 80 years was more than 10 times greater than the risk for persons aged 20-29 years. All deaths occurred among persons aged > or = 30 years. The case-fatality rate (overall: 25%) increased with age, from 11% in persons aged 30-49 years to 54% in persons aged > or = 80 years. Only 12% of all patients were reported to have received a primary series of tetanus toxoid before onset of illness. For 77% of patients, tetanus occurred after an acute injury was sustained. Of patients who obtained medical care for their injury, only 43% received tetanus toxoid as part of wound prophylaxis. INTERPRETATION: The epidemiology of reported tetanus in the United States during 1991-1994 was similar to that during the 1980s. Tetanus continued to be a severe disease primarily of older adults who were unvaccinated or inadequately vaccinated. Most tetanus cases occurred after an acute injury was sustained, emphasizing the need for appropriate wound management. ACTIONS TAKEN: In addition to decennial booster doses of tetanus-diphtheria toxoid during adult life, the Advisory Committee on Immunization Practices (ACIP) recommends vaccination visits for adolescents at age 11-12 years and for adults at age 50 years to enable health-care providers to review vaccination histories and administer any needed vaccine. Full implementation of the ACIP recommendations should virtually eliminate the remaining tetanus burden in the United States.

Hepatitis E among U.S. travelers, 1989-1992 -- Surveillance of deaths attributed to a Nor'easter -December 1992 -- Respiratory syncytial virus outbreak activity-United States, 1992 -- Condom use and sexual identity among men who have sex with men-Dal...